[for-linus][PATCH 3/3] tracing/histograms: Return an error if we fail to add histogram to hist_vars list

From: Steven Rostedt
Date: Sun Jul 23 2023 - 16:07:06 EST


From: Mohamed Khalfella <mkhalfella@xxxxxxxxxxxxxxx>

Commit 6018b585e8c6 ("tracing/histograms: Add histograms to hist_vars if
they have referenced variables") added a check to fail histogram creation
if save_hist_vars() failed to add histogram to hist_vars list. But the
commit failed to set ret to failed return code before jumping to
unregister histogram, fix it.

Link: https://lore.kernel.org/linux-trace-kernel/20230714203341.51396-1-mkhalfella@xxxxxxxxxxxxxxx

Cc: stable@xxxxxxxxxxxxxxx
Fixes: 6018b585e8c6 ("tracing/histograms: Add histograms to hist_vars if they have referenced variables")
Signed-off-by: Mohamed Khalfella <mkhalfella@xxxxxxxxxxxxxxx>
Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
---
kernel/trace/trace_events_hist.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index c8c61381eba4..d06938ae0717 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -6668,7 +6668,8 @@ static int event_hist_trigger_parse(struct event_command *cmd_ops,
goto out_unreg;

if (has_hist_vars(hist_data) || hist_data->n_var_refs) {
- if (save_hist_vars(hist_data))
+ ret = save_hist_vars(hist_data);
+ if (ret)
goto out_unreg;
}

--
2.40.1